Register clear symbol printing mechanism for calculating machine



Oct. 21, 1958 Original Filed Jan. 29. 1954 H. J. CHALL REGISTER CLEAR SYMBOL PRINTING MECHANISM FOR CALCULATING MACHINE 13 Sheets-Sheet 1 Oct. 21, 1958 I H. J. HALL 2,857,098

REGISTER CLEAR SYMBOL PRINTING MECHANISM FOR W CALCULATING MACHINE Original Filed Jan. 29. 1-954 13 Sheets-Sheet 2 II III] I [II III YIIIUIIIIIIIIIIIII II 8 N a f 0- N Q & Q

EII3 -E Oct. 21, 1958 H. J. CHALL REGISTER CLEAR SYMBOL PRINTING MECHANISM FOR CALCULATING MACHINE 13 Sheets-Sheet 5 Original Filed Jan. 29. 1954 Oct. 21, 1958 H. J. CHALL REGISTER CLEAR SYMBOL PRINTING MECHANISM-FOR CALCULATING MACHINE 13 Sheets-Sheet 4 Original Filed Jan. 29. 1954 now I I! ON Oct. 21, 1958 H J CHALL 2,857,098

REGISTER CLEAR SYMBOL PRINTING MECHANISM FOR CALCULATING MACHINE 13 Sheets-Sheet 5 Original Filed Jan. 29. 1954 Oct. 21, 1958 H. J. CHALL 2,357,093

REGISTER CLEAR SYMBO RINTING MECHANISM FOR CA E LCULA G MACHIN Original Filed Jan. 29. 1954 15 Sheets-Sheet 6 Oct. 21, 1958 H. J. CHALL REGISTER CLEAR SYMBOL PRINTING MECHANISM FOR CALCULATINGMACHINE l3 Sheets-Sheet 7 original Filed Jan. 29. 1954 Oct. 21, 1958 H. J. cHALL REGISTER CLEAR SYMBOL PRINTING MECHANISM FOR CALCULATING MACHINE 1s Sheets-Sheet 8 Original Filed Jan. 29. 1954 H. J. CHALL 2,857,098 REGISTER CLEAR SYMBOL PRINTING MECHANISM FOR ACHINE CALCULATING M 13 Sheets-Sheet 9 Oct. 21, 1958 Original-Filed Jan; 29.1954

[Ill/[11111III/UIIIIIIIIII IIII FIE-E- ""Oc f. 21, 1958 H. J. CHALL BEGISTERCLEAR SYMBOL PRINTING MECHANISM FOR CALCULATING MACHINE Original Filed Jan. 29. 1955. I 13 Sheets-Sheet 10 FII5 15 Oct. 21, 1958 H. .1. CHALL 2,857,098

REGISTER CLEAR SYMBOL PRINTING MECHANISM FOR CALCULATING MACHINE Original Filed Jan. 29. 1954 15 Sheets-Sheet 11 Oct. 21,1958 2,857,098

H. J. CHALL REGISTERCLEAR SYMBOL PRINTING MECHANISM FOR Original Filed Jan. 29. 1954 CALCULATING MACHINE l5 Sheets-Sheet 12 Oct. 21, 1958 H. J. CHALL REGISTER CLEAR SYMBOL PRINTING MECHANISM FOR CALCULATING MACHINE l3 Sheets-Sheet 13 Original Filed Jan. 29. 1954 m. H I IH United States Patent REGISTER CLEAR SYMBOL PRINTING MECHA- NISM FOR CALCULATING MACHINE Harold J. Chall, San Leandro, Califl, assignor to Friden, Inc., a corporation of California Original application January 29, 1954, Serial No. 407,016. Divided and this application March 8, 1954, Serial No. 414,598 i 8 Claims. (Cl. 235-60.17)

mcynmu on:

wowooQutnrsmww nism I. Algebraic sign sensing mechanism of the accumulator a; 17 J. Accumulator conditioning mechanism for total and subtotal printing 19 K. Tape feed mechanism 21 L. Subtotal printing cycle 23 M. Total printing cycle 26 N. Keyboard clearing cycle 27 0. Clear signal printing mechanism 28 1. Operation of the clear signal symbol printing mechanism 30 This invention relates to improvements incalculating machines, particularly adding machines, and is a division of my application S. N. 407,016, filed January 29, 1954, for Calculating Machine.

It is among the objects of the present invention to provide in a calculating or adding machine of the character disclosed in the above-referred-to parent application, a special printing mechanism which will print a special symbol following an accumulator clearing cycle of the machine to indicate that the accumulator has been cleared of the previous total and the machine is in readiness for a new series of entry values to be totalized; which normally prints a clear signal symbol during the first portion of a machine operating cycle immediately following a total taking cycle, but-is disabled from printing when the cycle immediately following a total taking cycle is another total taking cycle or a machine clearing cycle; which is spring-urged in its printing movement, is placed in a cocked condition during the total taking cycle and is normally released for printing and restored to its latched condition during the machine operating cycle immediately following an accumulator clearing, total taking cycle; which is fully automatic in operation and independent of the remainder of the printing mechanism of the calculating machine; and which provides a distinctive printed symbol spaced from the right-hand end of the first row of entry value figures following an accumulator clearing cycle of the machine.

Other objects and advantages will become apparent from a consideration of the following description and the appended claims in conjunction with the accompanying drawings wherein:

' Fig. 1 is a somewhat diagrammatic perspective view showing the several control keys, the cam shaft clutch and the motor controlling switch, and the mechanism operated by the control keys for closing the motor switch and conditioning the clutch for a single rotation of the cam shaft whenever any one of the control keys is depressed;

Fig. 2 is a front elevational view showing the machine cam shaft, the cams carried by the cam shaft, the location of the various cams along the cam shaft, and the form in plan view of the various cams; i

Fig. 3 is a view showing a portion of the printing mechanism and particularly the print wheels, the print wheel drive and the operating mechanism for the print wheels;

Fig. 4 is an elevational view of the actuator sector trail and lead cams, a print controlling cam and tenscarrying accumulator operating cam, and the mechanisms operated by these several cams; 1

Fig. 5 is a left side elevational view of the zero foil releasing cam for the printing mechanism and the mechanisms operated by this cam;

Fig. 6 is a general illustration of the ribbon shifting and tape feeding mechanism of the machine;

Fig. 7 is an elevational view from the left-hand side of the machine, showing the crank for operating the return mechanism of the'shiftable selector unit, the positive andnegative transmission gear locking cam, the crank pin for releasing the control keys at the left-hand side of the keyboard, and the-print controlling cam, together with the mechanismsoperated by'the several cams;

Fig. 8 is a cross-sectional View of the accumulatonthe positive gear transmission mechanism, the negative gear transmission mechanism, and the immediately associated parts of the machine;

Fig. 9 is a side elevational view of the accumulator Fig. 10 is a side elevational View from the right-hand sideof the machine showing the totaliand subtotal printing cams and the accumulator operated mechanism for sensing the algebraic sign of the 'total carried in the accumulator and placing the machine in condition to read out either a positive or a negative total or subtotal;

Fig. 11 is a left side elevational View of 'the tenstransfer cam and associated mechanism for operating the accumulator tens-transfer actuating bail;

Fig. 12 is a longitudinal cross-sectional view of the machine, showing in elevation the total and subtotal control keys mounted at the front end of the machine key-board, together with the mechanism operated by these keys for initiating operating cycles of the machine and mechanism for blocking the simultaneous depression of two or more control keys;

Fig. 13 is a fragmentary top plan view of the total and subtotal control mechanism, illustrated in Fig; 10, taken from a plane indicated by the line 1313 of Fig. 10; and

Fig. 14 is a somewhat diagrammatic perspective view, illustrating the clear signal symbol printing mechanism of the machine, which mechanism operates to print a clear signal symbol on the printing tape following a machine clearing, total printing cycle.

In Figs. 3 to 11, inclusive, a line AA, indicating a reference plane parallel to the keyboard of the machine, has been drawn through the axis of the cam shaft of the machine, and a second line BB has been drawn through the axis of shaft 135 perpendicular to the line AA and indicates a second reference plane perpendicularly intersecting the plane indicated by the line AA along the axis of shaft 135.

A. POWER CYCLE MECHANISM The power cycle mechanism of the machine includes an electric motor, not illustrated, mounted in the rear portion of the machine and provided with a normally open switch 139 controlling the motor operation, a cam shaft 135 carrying disk type cams, as shown in Fig. 2, at locations spaced-apart therealong, a one rotation clutch mechanism, generally indicated at 150, mounted on the right-hand end of the cam shaft, and a speed reducing gear train, not illustrated, drivingly connecting the motor shaft to the clutch 150 and through the clutch to the cam shaft 135.

For a more detailed illustration and description of the power cycle mechanism reference may be had to my application S. N. 407,016 referred to above.

1. Cam and cam shaft assembly Fig. 2

The cam shaft 135, in addition to the clutch control cam disk 157, the antibacklash cam disk 160 and the shiftable selector unit return arm 137, carries at locations spaced-apart therealong, machine operating cam disks, as illustrated in Fig. 2, and including, from left to right along the cam shaft, the return arm 137 and arm carried pin 138 for returning the shiftable selector unit to its home position, a pendant gear, or shiftable transmission latching cam, 170, a zero foil actuating cam 171 for the printing mechanism, a printing cam 172, a tens-carry actuating cam 173 for the machine accumulator, an actuator operating trail cam 174, an actuator operating lead cam 175, an actuator sector aligner cam 176, a subtotal cycle cam 177, a total cycle cam 178, and a transmission shifting cam 179.

All of the cams are shown in Fig. 2 in their home, or full-cycle, position, from which they turn in a clockwise direction when viewed from the right-hand side of the machine.

B. ACTUATOR MECHANISM The machine has an actuator mechanism, as shown in Figs. 3 and 4, comprising an axle shaft 185, journalled at its ends in upright frame plates of the machine and extending transversely of the machine above, and substantially parallel to, the cam shaft 135; actuator sectors 188 journalled in side-by-side, or ordinal, arrangement on the shaft 185; and an operating bar, or bail, 192 extending through the actuator sectors in spaced and parallel relationship to the axle shaft 185.

Each actuator sector is substantially of the shape of a section of a circle and the axis of the axle shaft 185 extends through the centers of the hypothetical circles of which the corresponding sectors constitute sections. Gear teeth 189 are provided on the arcuate edges of the actuator sectors, and each sector is provided with an elongated opening 190 having a longitudinal curvature centered on the axis of shaft 185. The sectors may also be provided with weight reducing openings, if desired.

A yoke 194, of somewhat elliptical shape, surrounds the cam shaft 135 and the actuator trail and lead cams 174 and 175. The yoke has an upwardly and forwardly projecting extension 195 pivotally mounted on a fixed cam follower shaft 196, which extends transversely of the machine above, and forwardly of, the cam shaft 135, which follower shaft is supported in the side and intermediate plates of the machine frame. An arm 197 extends forwardly from the extension 195 and is pivotally connected by a spacing pin 198 to the distal end of one leg 199 of a ribbon feed actuating bellcrank lever 200, rockably mounted on the cam follower supporting shaft 196. The other leg 201 of bellcrank lever 200 extends upwardly from shaft 196 and is connected at its upper end to the forward end of a link 202 which drives the ribbon feed of the printing mechanism.

An arm 203 extends rearwardly from the rearward end 01' the yoke 194 and is pivotally connected at its rearward, or distal, end to the lower end of a link 204, the 1 upper end of which is connected to the actuator bail 192.

The yoke carries, on its upper side, a cam following roller 205 riding on the peripheral edge of the actuator trail cam 174 and on its lower side a cam following roller 206 riding on the peripheral edge of the actuator lead cam 175, the yoke being disposed between the cams 174 and 175. The roller 205 projects from the right-hand side of the yoke while the roller 206 projects from the left-hand side of the yoke.

With this arrangement, the bail 192 is positively moved both downwardly and upwardly and, during an operating cycle of the machine, is first moved to its lower position, is maintained in its lower position for a predetermined time interval, and is then restored to its upper position.

A corresponding latch lever 208 is disposed adjacent one side of each actuator sector 188 and is pivoted at its upper end to the sector near the upper radial edge of the sector by a pivotal connection 209 and extends from the pivotal connection along the opening 190 in the actuator sector and past the side of the bail 192 remote from the axle shaft 185. The latch lever is angularly bent intermediate its length to provide, at the side thereof adjacent the bail 192, a concave seat 210 which receives a roller 210 rotatably mounted on the bail 192, the roller 210' being received in the corresponding seat 210 when the bail is in its upper limiting position relative to the corresponding sector 188. The latch lever is resiliently held in engagement with the bail by a spring 211 connected between the sector 188 and the distal end of an arm 212 projecting angularly from the pivoted end of the lever 208. The portion of the lever 208 between the seat 209 and the free end of the latch lever constitutes a longitudinally curved tail portion 213 directed from the bail 192 toward the. shaft 185.

When the bail 192 moves upwardly relative to the actuator sectors 188, it comes into engagement with abutment formations 214 at the upper ends of the openings 190 in the sectors, simultaneously moving into the seats 210 of the latch levers 208, and then moves the actuator sectors upwardly until the upper radial edges of the sectors abut against a stop bar 215 in the upper, or full-cycle, position of the actuator sectors.

C. PRINTING MECHANISM 1. Print wheels and gear mechanism Fig. 3

The printing mechanism, generally indicated at 216, is disposed above the actuator mechanism with its orders in alignment with corresponding orders of the actuator mechanism. A plurality of print wheel drive gears 217 are journalled on a drive gear shaft 218 which extends transversely of the machine above and parallel to the cam shaft 135. The gears 217 are disposed in side-by-side, or ordinal, arrangement along the shaft 218 and the number of cylindrical shape provided with a peripheral notch 220, 188. Each gear 217 includes a central hub portion 219 of cylindrical shape provided wtih a peripheral notch 220, the purpose of which will presently be explained.

A plurality of print wheel carriers 221 are rockably mounted intermediate their length on a fixed shaft 222 which extends transversely of the machine in spaced and parallel relationship to the shaft 218. Each carrier 221 includes a pair of parallel arms 223 and 224 with the pairs of arms arranged in side-by-side, or ordinal, arrangement along the shaft 222 and in alignment with corresponding drive gears 217 and actuator sectors 188. 1

Both arms 223 and 224 extend upwardly from the shaft 222. Near the upper end of the arm 224, a pivot pin, or axle, 225 extends transversely through the two arms of each pair of arms 223 and 224 and carries an idler gear 226 which meshes with the corresponding drive gear 217. The arm 223 of the carrier pair 221 is extended upwardly and forwardly beyond the upper end of the arm 224 and carries an axle pin 227 spaced above the axle pin 225. A print wheel gear 230 is journalled on the axle pin- 227 and includss a spur gear portion 231,

the teeth of which mesh with the teeth of the idler gear 226 mounted. in the same carrier and which is formed on one side of a print wheel portion 232 having printing bosses 233 projecting from the periphery thereof at uniformly spacedangular intervals therearound. It will be noted that the printing bosses 233 are spaced apart and that the outer surfaces of these bosses are made concave in a direction circumferentially of the printing wheel so that the outer surfaces of the bosses will fit against the cylindrical surface of a printing platen. 242, presently to be described.

2. Zero foil latch mechanism Fig. 3

Each of the arms 223. is'provided with anextension 235 directed forwardly from the pivot shaft 222 and overlying one side of the outer portion of the corresponding drive gear 217 to serve as a guide for maintaining the corresponding drive gears 217 and idler gears 226 in meshing alignment with each other. The arm 223 is also extended forwardly of the print wheel axle pin 227, as indicated at 236, and this forward extension is notched out to provide, at its lower portion, alatchshoulder 237 facing upwardly and forwardly. A- plurality of irregularly-shaped zero foil latch levers 238, equal in number to the number of print wheel drive gears 217 and print wheel carriers 221, are pivotally mounted intermediate their length on a fixed shaft 239 which extends transversely of the machine in spaced and parallel relationship to shafts 218 and 222. Each of these zero foil latch levers 238 has an upwardly directed arm 240, provided at its upper end with arearwardly directed detent formation 241 which engages the shoulder 237 on the corresponding print wheel carrier arm 223 to releasably latch the corresponding print wheel in nonprinting position in which it is spaced from the associated printing platen 242. The latch levers 238 are received in corresponding transverse notches, or recesses, in a comb bar 243 which extends transversely of the machine above and parallel to the shaft 239 to maintain these latch levers in properly spaced relationship to each other. Each lever has a forwardly directed lever arm 244 and a rearwardly directed arm 245, the rear end portion of which is disposed against the same side of the corresponding drive gear 217 against which the forward extension 235 of the carrier arm 223 is disposed. A spring 246 is connected between the distal end of each forwardly directed latch lever arm 244 and-a fixed spring attaching bar 247 extending transversely of the machine above, and substantially parallel to, the shaft 239, these springs urging the corresponding latch levers to rock in a clockwise direction, as illustrated in Fig. 3. Each rearwardly directed latch bar arm 245 has on its rearward end a downwardly directed detent 248, which drops into the notch 220 in the corresponding print drive gear wheel hub 219 to free the latch arm for clockwise rocking movement by the associated spring 246 to a position in which the latching detent 241 at the upper end of the upwardly directed arm 240 of the latch lever engages over the corresponding shoulder 237 on the carrier arm 223.

A latch releasing bail 250 extends through slots in the intermediate frame plates and across the upper edges of the forwardly directed arms 244 of the latch levers 238. The bail 250 is supported at its ends in the upper ends of a pair of arms, one of which is illustrated in Fig. 5 and designated at 252, pivotally mounted at locations spaced below the bail 250 on the intermediate frame plates, as indicated at 253 for the arm 252, so that the bail 250 can swing forwardly and downwardly and upwardly and rearwardly in the frame plate slots.

The arm 252, as shown in Fig. 5, is extended downwardly beyond its pivotal mounting 253 upon the inter- 6 mediate frame plate and is provided at its lower end with a face which abuts a pin 254 located on cam follower lever 255. The cam follower lever 255 is pivotally mounted intermediate its length on the transverse shaft 196, and at its upper end is in engagement with the forward side of the arm 252. At its lower end, the lever 255 carries a cam following roller 257 which rides on the peripheral edge of the zero foil, cam 171 mounted on the cam shaft 135. The zero foil cam 171 is soshaped that during approximately the first degrees of a machine cycle, during which time the actuator sectors 188 are undergoing their downward stroke, the bail 250 is held down on the forwardly directed arms 244 of the latch levers 238, holding the latch lever detents 241 out of engagement with the latching shoulders 237 on the print wheel carrier arms 223. This maintains the latch lever detents 248 out of the notches 220 in the print wheel drive gear hubs 219 and frees the drive gears for rotational movement. Near the end of the first half and beginning of the second half of the machine cycle, while the actuator sectors are being held in their limiting downward positions, the cam follower 257 rides into a low portion of the cam 171. A tension spring 260, connected between the upper end of the bail supporting arm 252 and the machine frame, raises the latch lever bail 250 away from the latch lever arms 244 and thereby conditions the latch levers to move into engagement with the corresponding shoulders 237 under the actuation of the corresponding latch lever springs 246.

During the downward stroke of the actuator sectors and while the latch levers 238 are held out of engage ment with the notches 220 in the drive gear hubs 219 by the bail 250, those drive gears in alignment with selector sectors which have been manually set to numeral values will be rotated away from their 0 positions in a manner presently to be described. When the actuator bail 192 approaches the end of its downward movement and the bail 250 is moved to release the latch levers 238, the notches in the drive gears, which have been rotated from their 0 positions, will be moved out of registry with the corresponding zero foil latch lever detents 248. These detents will not be able to re-enter the corresponding. notches 220 and will be held on the cylindrical peripheral surfaces of the corresponding hub formations 219. In that event, the corresponding latch lever abutments 241 will be held out of engagement with the shoulders 237 of the corresponding print wheel carriers 221, leaving these carriers free to rock the print wheels 230 carried thereby toward the platen 242 during the printing operation, presently to be described.

The upwardly directed arm 240 of each latch lever 238 has near its upward end a forwardly directed projection 261, the outer end portion of which is laterally directed to the left, as viewed from the front of the machine, and overlies the outer end of the projection 261 on the next latch lever to the left, these forward extensions being omitted from the upwardly projecting arms of the first two latch levers at the right-hand end of the assembly. The arrangement is such that if any print Wheel drive gear to the left of the first two gears at the right-hand end of the assembly is moved away from its 0 position, all of the latch levers to the right of such drive gear will be held by the zero foil projections 261 out of latching engagement with the corresponding shoulders 237 on the print wheeel carrier arms 223 and the print wheels to the right of the indicated drive gear will be free to move in a printing operation. Since the drive gears to the left of the indicated drive gear have not been moved and still have their hub notches 220 in registry with the zero foil latch lever detents 248, and since the latch levers to the left are not restrained by the projections 261, these latch levers to the left of the indicated drive gear will be moved by their springs 246 into latching engagement with the corresponding shoulders 237 to hold the corresponding print 7 wheels against printing movement so that the printing mechanism will not print zeros to the left of the highest order of the numeral entry made into the machine by the keyboard and selection mechanism, as previously explained.

When the printing operation is completed near the middle of the machine cycle, the bail 250 will have been moved downwardly by the cam 171 to raise all of the latch lever detents 248 out of the corresponding notches 220 in the print drive gear hubs 219, thereby freeing the print wheel drive gears for rotational movement by the downward stroke of the actuator sectors during the first portion of the next operating cycle of the machine.

The manner in which a driving connection is provided between the actuator sectors 188, the print wheel drive gears 217 and the selector sectors 33 Fig., 8, will be described in detail in the next following section dealing with the positive, pendant gear transmission mechanism.

3. Printing operation Fig. 3

The lever arm 224 of each print wheel carrier 221 is provided with a rearwardly directed extension, or tail portion, 263. A tension spring 264 is connected between the rear end of each rearward extension 263 and the machine frame, and is effective, when the print wheel carrier is released, to rock the corresponding print wheel carrier 221 about the shaft 222 in a direction such that the associated print wheel 230 is moved rearwardly to strike the adjacent, forward portion of the cylindrical surface of the platen 242.

A bail cross member in the form of a rod 265 extends transversely of the machine below the rearward extensions 263 of the carrier levers 224 and is supported at its ends in the rearward ends of a pair of bail supporting arms 266 and 267, as shown in Figs. 3, 6 and 7. At their forward ends, the arms 266 and 267 are pivotally mounted on the carrier supporting shaft 222. The arm 266 is provided, at a location spaced somewhat above and forwardly of the bail 265, with a laterally projecting stud 268 which preferably carries a sleeve, or roller, 269.

A bellcrank lever 270, Fig. 7, is pivotally mounted at its knee on the axle shaft 218 of the print wheel drive gears 217 and has the rearward or distal end of one of its arms 271 underlying the stud carried roller 269. The other arm 272 of this bellcrank lever extends downwardly and rearwardly from the shaft 218 and to a location opposite the cam shaft 135 and carries on its lower, or distal, end a cam following roller 273 which rides on the peripheral edge of the print cam 172.

The print cam 172 is so shaped that during the major portion of a machine cycle the bail 265 is supported in its upper limiting position in which it holds the lever extensions 263 upwardly and renders the springs 264 ineffective to move the print wheels 230 toward the platen 242. The cam 172 is provided with a recess 274 having an abrupt leading edge and a sharply sloping trailing edge, and of restricted angular extent, into which the cam follower 273 drops during a time interval in which the actuator sectors 188 are retained at the end of their downward stroke, as described above. Such action of bellcrank 270 provides for sharply and momentarily moving the bail 265 downwardly, away from the bottom edges of the carrier lever extensions 263 and enabling the springs 264 to rock the carriers 220, which have been freed from their associated latch levers 238 in a direction to strike the print wheels 230 against the platten 242. After the free print wheels have been moved to strike the platen 242, they are immediately returned to their home, or full-cycle, position by reason of the limited angular extent of the recess 274 in the printing cam 172.

The machine has a manually settable selection mechanism, including differentially settable selector racks, addition, subtraction, repeat addition and print only keys, and mechanisms conditioned by these several keys to establish the corresponding operating cycles of the machine, all as fully disclosed in my copending application S. N. 407,016 referred to above, in addition to a total 'taking key, a subtotal taking key, a keyboard clearing key and mechanisms conditioned by these keys to establish the corresponding operating cycles, as will be more fully explained hereafter. The machine also ineludes an accumulator, Fig. 8, which accumulates true positive and negative totals, and positive and negative gear transmission mechanisms, which selectively drivingly interconnect the actuator mechanism and the accumulator in accordance with the additive or subtractive nature of a value entered into the accumulator or the positive or negative nature of the algebraic sign of the balance in the accumulator, the positive gear transmission being also used to connect the actuator mechanism to the selector mechanism during the first portion of an addition, repeat addition, subtraction or print only cycle of the machine.

D. POSITIVE TRANSMISSION GEAR MECHANISM The positive transmission gear mechanism 330 is disposed between the actuator mechanism and the selector mechanism 11 and comprises a bail or cage having parallel legs, as indicated at 331 in Fig. 8, spaced apart a distance somewhat greater than the length of the actuator mechanism and interconnected by a rigid cross member 332 and spaced apart and parallel gear shafts 334, 335 and 336. A transmission shifting element 333, as shown in Figs. 6 and 10, extends angularly from the upper end of one of the legs above the top gear shaft 334 and is used to shift the positive gear transmission mechanism.

The cross member 332 provides a rigid cage or carriage for the transmission gears and the three gear shafts, or axles, 334, 335, and 336 extend transversely of the space between the-bail legs 331 in spaced-apart and parallel relationship to each other and are mounted at their ends in the corresponding bail legs 331. A plurality of transmission gears 337 are journalled on the upper gear shaft 334 in side-by-side, or ordinal, arrangement, the number of these gears being equal to the number of actuator sectors 188 and the gears being constantly in mesh with the corresponding actuator sectors 188 and with the corresponding print wheel drive gears 217, as is shown in Fig. 3. A plurality of intermediate, or reversing, gears 338 equal in number to the number of selector sectors 33, are journalled in side-by-side, or ordin'al, arrangement on the intermediate gear axle 335 and these gears mesh respectively with the gears 337. A plurality of gears 340 are journalled on the gear axle 336, also in side-by-side, or ordinal, arrangement, the number of these gears also being the same as the number of selector sectors. The gears 340 mesh with the corresponding intermediate, or reversing, gears 338. The gears 337, 338 and 340 are preferably all ten-tooth gears of the same size, with teeth of the size of the teeth on the selector sectors 33 and on the actuator sectors 188.

The upper gear axle 334 is extended beyond the legs of the gear carrying cage and is mounted at its ends in the intermediate frame plates of the machine so that the entire cage can swing about the axis of the axle 334 carrying with it the gear axles 335 and 336 and the gears 338 and 340.

In the addition and subtraction cycles of the machine, the cage of the positive transmission mechanism is rocked by the cam 179 to the position for meshing the gears at the free end of the cage with the selector sectors and this clockwise movement of the cage brings the transmission gears 340 corresponding to the number of selector sectors which have been stepped to the left during the entry of the figure to be added or subtracted into the selector mechanism, into mesh with the corresponding selector sectors 33 during the first portion of the machine cycle in which the actuator segment bail 192 is given its down ward stroke. During the downward stroke of the actuamass ator hail, the selector sectors, which have been manually set and which are engaged or meshed with corresponding positive transmission gears 350, will be returned to. their home, or 0, position at which they are stopped by the stop bar 27. During the downward movement of the corresponding actuator sectors, the print Wheels 230 in alignment with these sectors are rotated by the corresponding gears 337, 217 and 226 to bring the numerals embossed on the print wheels 230, which correspond to the num bers for which the corresponding selector sectors are set, in position to impinge the platen 242 during the printing movement of the print wheels, as described above.

E. ACCUMULATOR MECHANISM (Figs. 8, 9 and 10) The accumulator mechanism of the adding machine is generally indicated at 390 and particularly illustrated in Figs. 8, 9 and 10. This mechanism is provided as a unitary structure which is installed in the machine through an opening 391 in the machine base 392 and has a rigid frame including rackets 393 and 394 which are disposed one along each side of the opening 391 and extend upwardly through the opening. These brackets have perpendicularly ofiset, apertured lugs, which extend into recesses in the base at the corresponding sides of the opening 391 and are secured to the base by screw fasteners, as indicated at 395. The frame also includes left and right end plates 396 and 397, disposed in spaced-apart and parallel relationship to each other, and a plurality of separator plates 398 uniformly spaced apart between the end plates 396 and 397 and disposed in parallel relationship to each other and to the end plates. The end plates and the separator plates are provided with aligned apertures, including one series of aligned apertures near the bottom edges and the front ends of these plates, and one set of aligned apertures near the bottom edges and the rear ends of the plates. A supporting bar 400 of rectangular crosssectional shape extends through the series of apertures near the front edges of the plates, while a similar bar 401 extends through the series of apertures near the rear edges of the plates. The bars 400 and 401 are secured to the upstanding portions of the brackets 3 93 and 3.94 by suitable means, such as the screw fasteners 402 extended through apertures in the brackets and threaded into tapped holes in the corresponding ends of the bars.

Suitable clamping means, such as a base plate 403, as illustrated in Fig. 8, r clamping strips, underlie the bottom edges of the plates 396, 397 and 3% parallel to the supporting bars 400 and 401. Screw fasteners 404 extend through apertures in the clamping means and are threaded into tapped holes extending transversely of the bars 400 and 401 to clamp the end plates and spacer plates rigidly in their position on the supporting bars. The plates are also reinforced in their spaced and parallel relationship to each other by various shafts and through pins, as will become apparent during the following description of the accumulator mechanism.

A main axle shaft 405 extends transversely through the plate assembly intermediate the height of the plates and is secured at its ends in the end plates 396 and 397.=

A plurality of accumulator gears 406 are mounted in side-by-side, or ordinal, relationship on the shaft 405 and are disposed one gear in each space between the adjacent spacer plates 398 and one gear between each outside spacer plate 396 and 397 and the adjacent end plate,-

there being eleven of these accumulator gears, or one more than the selector sectors. Each accumulator gear 406 has twenty gear teeth 407 uniformly spaced around its periphery and a tens-transfer cam structure 408 is disposed against one side of each accumulator gear and rigidly secured to the gear for rotation therewith.

Each tens-transfer cam structure 408 comprises a bar extending diametrically of the associated accumulator gear and having an enlarged and apertured center por- 10 beveled end portions terminating in blunted points disposed in alignment with interdental spaces at diametrically opposite sides of the gear.

A drive gear shaft 410 extends transversely through the plate assembly above, and parallel to, the shaft 405 and this shaft 410 also extends, at its ends, outwardly of the outer sides of the end plates 396 and 397 of the plate assembly. Accumulator drive gears 411 are journalled in side-by-side, or ordinal, arrangement on the shaft 410, there being eleven of these gears disposed, one in each space between adjacent plates of the plate assembly and meshing with the corresponding accumulator gear 406. Each drive gear has ten gear teeth 412 so that it requires two rotations of a drive gear to complete one rotation of the associated accumulator gear.

A detent shaft 414 extends transversely through the plate assembly at the upper, width reduced end of the assembly. Detent pawls 415 are rockably mounted on the shaft 414 in ordinal arrangement along the shaft, there being one detent pawl for each of the accumulator drive gears 411. Each pawl has, at one end, a bearing portion 416 receiving the shaft 414, and at its other end, a V-shaped detent formation 417 which engages in the interdental space at the upper side of the associated drive gear 411 to hold the drive gear and corresponding accumulator gear against accidental rotation. Each pawl is resiliently held in movement resisting engagement with its associated drive gear, by a tension spring 418 connected between the pawl at a location intermediate the length of the pawl and a tie rod 419, which extends transversely of the plate assembly below and parallel to the detent shaft 414.

With the above-described arrangement it will be apparent, that when the positive gear transmission 330 is rocked, as described above, to mesh its gears 340 with the accumulator drive gears 411 during the upward or return stroke of the actuator sectors 188, the drive gears 411 will be rotated in an additive or clockwise direction and will impart an opposite or counterclockwise rotation to the associated accumulator gears 406.

F. NEGATIVE TRANSMISSION GEAR MECHANISM Means are also provided for rotating the accumulator gears in a negative or subtractive direction during the upward stroke of the actuator sectors and this means includes a negative or subtractive gear transmission assembly, generally indicated at 420.

The gear assembly 420 comprises a bail having parallel legs 421 spaced apart a distance at least as great as the length of the actuator mechanism and the accumulator mechanism and connected by a cross Portion 422 extending transversely across the space between and joined at its ends to the legs 421. Spaced-apart and parallel gear shafts 423 and 424 are mounted at their ends in the bail legs 421 and extend across the space between these legs. A plurality of ten-toothtransrnission gears .425 are mounted in side-by-side, or ordinal, arrangement on the shaft 423, while a plurality of similar, ten-tooth transmission gears 426 are mounted in side-by-side, or ordinal, arrangement on the shaft 424 and mesh with corresponding gears 425.

It will be noted that the positive gear transmission 330 has an odd number of gear sets, three such sets being shown in the accompanying drawings, while the negative gear transmission 420 has an even number of gear sets, two such gear sets being illustrated. This provides an arrangement wherein the positive gear transmission will rotate the accumulator drive gear 411 in one direction to add a positive or additive value to the accumulator, while the negative transmission 420 will rotate the drive gears in the opposite direction to apply a subtractive or negative value to the accumulator.

tion through which the shaft 405 extends, and double The bail legs 421 of the negative transmission bail extends beyond the gear shaft 423 in a direction away' from the gear shaft 424, the bail being mounted in spaced-apart pivot studs 427 having a common axis which extends through the bail legs at the ends thereof at the side of the shaft 423 remote from the shaft 424. The studs 427 are mounted in the intermediate frame plates 186 and 187 of the machine to provide a pivotal mounting for the negative gear transmission parallel to, but spaced from, both of the gear shafts 423 and 424.

G. TENS-CARRYING MECHANISM OF THE ACCUMULATOR As in all mechanical accumulators, it is necessary to provide mechanism which becomes effective, when any particular accumulator gear advances past its 9 and through its position, to advance the accumulator gear of the next highest order an angular extent corresponding to one gear tooth or a single unit space. This is a tens-transfer mechanism and in the accumulator of the present invention this mechanism is provided in two symmetrical parts located at diametrically opposite sides of the accumulator gears so that it can accomplish its tens-transfer function in either a positive or negative rotational direction of the corresponding accumulator gears depending upon whether a positive or a negative entry is being stored in the accumulator.

Shafts 438 and 439 extend transversely of the accumulator plate assembly below the accumulator gears 406 and in spaced and parallel relationship to each other and the accumulator gear shaft 405. A number of bellcrank levers 440, equal in number to the number of accumulator gears 406, are pivotally or rockably mounted at their knees on the shaft 438 in side-by-side, or ordinal, arrangement. Each of these bellcrank levers has one arm 441 extending downwardly and rearwardly toward the complementary shaft 439 and terminating substantially midway between the shafts 438 and 439, and has an arm 442 projecting upwardly and forwardly from the shaft 438 and provided near its upper end with a rearwardly directed hook formation 443. Bellcrank levers 444 are rockably mounted at their knees on the shaft 439 in side-by-side, or ordinal, arrangement relative to each other and are also equal in number to the number of accumulator gears 406. Each lever 444 has a leg 445 extending upwardly and forwardly toward the shaft 438 and terminating medially of the distance between the shafts 438 and 439, it being noted that the distal ends of the lever arms 441 and 445 overlap between the lever supporting shafts 438 and 439. Each lever 444 also has a rearwardly directed arm 446 provided near its distal end, and on its upper edge is provided with an upwardly directed hook formation 447. Tension springs 448 extend between the hook formation 443 and 447, each spring being connected, at one end, to the hook forma tion 443 on a bellcrank lever 440; and at its other end, to the hook formation 447 on the opposite bellcrank lever 444 and tending to resiliently rock the two bellcrank levers toward each other about their pivotal mountings on the shafts 438 and 439.

A tens-transfer pawl 450 is pivotally mounted by a pivot connection 451 on the upper end of each bellcrank leg 442 and has an angularly-shaped arm 452 directed toward the aligned accumulator gear 406 and terminating at its distal end in a nose formation 453 which will engage a tooth of the aligned accumulator gear and rotate the corresponding gear through one unit space in a positive entry direction when the bellcrank lever 440 is rocked about the shaft 438 by the spring 448 in a direction such that the hook formation 443 moves toward the hook formation 447 of the opposite bellcrank lever 444. Adjacent the nose 453, the arm 452 is provided with a terminal shoulder 454 which engages a stop bar 455 extending transversely through the accumulator plate assembly and limits the rotational movement imparted ordinal, arrangement relative to each other.

v to the accumulator gear by the nose 453 to a single unit space.

The axis of the stop bar 455 is in, or adjacent to, a plane including the axes of the accumulator gear shaft 405 and the bell-crank pivot shaft 438 intermediate the distance between the shaft 405 and the shaft 438 and this stop bar also serves as a tie rod to reinforce the accumulator plate assembly.

The pawl 450, in addition to the arm 452, includes a hook formation 456 which projects from the pawl radially of the pivotal connection 451 and in a forward direction, and which is connected by tension spring 457 to a lug 458 projecting radially from the forward edge of the bellcrank lever 440 adjacent the shaft 438. The spring 457 resiliently urges the pawl 450 to rotate in a direction to raise the nose 453 into engagement with the teeth of the aligned accumulator gear when the bellcrank 440 is rocked in a rearward direction by the spring 448. The pawl is also provided with a radially directed stop arm 459, the distal end of which engages a stop pin, or stud, 460 carried by the bellcrank arm 442 to limit rotational movement of the pawl 450 by the spring 457. The arm 452 of the pawl is provided intermediate the length of its upper edge with a latching shoulder 461.

Shafts 462 and 463 extend transversely of the accumulator plate assembly above the accumulator gear shaft 405 and near the front and rear edges, respectively, of the plate assembly. These shafts 462 and 463 are disposed in spaced and parallel relationship to each other and to the shaft 405. The shaft 462 is above the shaft 438, while the shaft 463 is above the shaft 439.

A plurality of latch levers 465 are rockably mounted each at its upper end on the shaft 462 in side-by-side, or These latch levers depend from the shaft 462 and each carries at its lower end an abutment formation 466 which engages the shoulder 461 on the corresponding transfer pawl 450 and holds the pawl in retracted position with its nose 453 spaced from the corresponding accumulator gear 406. Each latch lever 465 has, intermediate the length thereof and at the side thereof nearest the accumulator gears 406, a rearwardly extending nose formation 467 which abuts against a stop bar 468 when the lever is in latching engagement with its associated pawl 450 to limit rocking movement of the lever about the shaft 462 in a direction toward the accumulator gears. A tension spring 469 connected between the lower end portion of the latch lever 465 and a tie rod 470, extending transversely through the accumulator plate assembly between the lower end of the latch lever 465 and the accumulator gear assembly, resiliently urges the latch lever to rock toward the gear assembly.

A live pawl, or actuating dog, 472 is disposed against one side of each of the latch levers 464 and pivotally connected to the corresponding latch lever by a pivotal connection 473 located medially of the length of the latch lever. The actuating dog 472 is provided with an abutment formation 474 which projects radially from the pivotally mounted portion of the dog into the path of the outer end portions of the tens-transfer cam 408 carried by the corresponding accumulator gear and is also provided with a forwardly directed arm 475 connected near its distal end by a spring 476 to the upper end portion of the latch lever 465. The spring 476 resiliently urges the actuating dog 472 rotate relative to the associated latch lever 465 until a stop arm 477 on the actuating dog is brought to bear against a stud 478 projecting laterally from the corresponding latch lever 465. The stop arm 477 bears against the side of the stud 478 remote from the accumulator gear assembly so that, when the accumulator gear 406 is rotating in a positive, or counterclockwise, direction, as viewed in Fig. 8, and an end of the tens-transfer cam member 408 engages the abutment formation 474 applying pressure in a downward direction to this abutment formation, the actuating dog will not rock relative to the associated latch lever 465 but, the latch lever will be forced to swing away from the accumulator gear assembly releasing the abutment formation 466 on the lower end of the latch lever from the latching shoulder 461 on the associated pawl 450 to free the pawl 450 for rocking movement of this pawl and the associated bellcrank 440 about the shaft 438 in a direction to move the nose 453 against a tooth of an aligned accumulator gear and rotate the gear one unit space in the positive, or counterclockwise, direction.

The spring-biased pivotal connection between the tenstransfer pawl 450 and the associated bellcrank 440 permits the bellcrank lever and the pawl carried thereby to be returned from a gear moving position to their home, or full-cycle, position, as illustrated in Fig. 8, without imparting any rotation in a reverse or negative direction to the associated accumulator gear and the spring-biased, pivotal connection between the actuating dog 472. The associated latch lever 465 permits the end portions of the corresponding tens-transfer cam 408 to move past the abutment formation 474 of the actuating dog in a negative, or clockwise, direction without moving the associated latch lever 465 to release the corresponding tenstransfer pawl 450.

The nose 453 on each tens-transfer pawl 450 is offset laterally to the left from the abutment formation 474 of the actuating dog 472 mounted on the latch lever 465 holding the particular pawl so that, when the latch lever is released from its associated pawl by engagement of the tens-transfer cam 408 on the accumulator gear in alignment with the latch lever 465, the nose 453 will engage a tooth of the accumulator gear of the next higher order, that is, the accumulator gear immediately to the left of the gear carrying the tens-transfer cam which released the latch so that the gear of the next higher order will be advanced one unit space in the positive or additive direction.

A tens-transfer paw 485 is pivotally mounted on each of the negative bellcrank levers 444 and urged by a tension spring 486 connected between a hook formation on thepawl and a lug on the bellcrank lever to a rotational position in which the stop arm 487 on the pawl engages the stop stud 488 on the arm 446 of the lever 444. Each transfer pawl 485 carries a terminal nose formation 489 effective, when the arm 444 is rocked by the spring 448 toward the corresponding accumulator gear 406, to move the accumulator gear engaged by the particular nose 489 one unit space in a negative, or clockwise, direction, as viewed in Fig. 8. Each transfer pawl 485 is also provided with a terminal shoulder 490 which engages a stop bar 491 extending transversely of the accumulator plate assembly in spaced and parallel relationship to the stop bar 455 to limit swinging movements of the pawl 485 under the influence of spring 443 to an extent such that the nose 489 will move the corresponding accumulator gear one unit space only. The assembly of each negative bellcrank 444 and corresponding transfer pawl 485 is identical with the corresponding positive assembly including a bellcrank lever 440 and pawl 450, and the s ring-biased pivotal connection between the pawl 485 and the bellcrank 444 permits the pawl and bellcrank assembly to be returned to its home, or full-cycle, position after a gear rotating movement without imparting any rotational movement to the associated accumulator gear.

Negative latch levers 492 are pivotally mounted at their upper ends on the shaft 463 in side-by-side, or ordinal, relationship to each other and depend from the shaft 463 toward the corresponding transfer pawls 485. Each latch lever 492 carries on its lower end an abutment formation 493 which engages with the latching shoulder on the upper edge of the corresponding pawl 485 to releasably hold the pawl in its home, or full-cycle, position retracted from the corresponding accumulator gear. A tension spring 494 is connected between each latch lever 492 near the lower end of the lever and a tie rod 49S,

extending transversely of the accumulator plate assembly, resiliently urges the latch lever to swing about the'shaft 463 to its pawl latching position. A nose' formation 496, directed forwardly from the forward edge of'the lever 492, medially of the length of the lever, engages a stop bar 497 extending transversely of the accumulator plate assembly to stop the spring induced swinging movement of the latch lever 492 when the lever has been brought by the spring to its latching position.

A latch lever actuatingpawl 498 is pivotally mounted on each latch lever 492 medially of the length of the latch lever, by a pivotal mounting 499. A tension spring 500 connected between one end of the dog 498 and the upper end portion of the lever 492 resiliently urges the dog to rotate relative to the associated lever 492 until the stop arm 501 on the dog is brought to bear against the outer side of the stop lug 502 extending laterally from the upper portion of the latch lever 492.

The dog 498 carries an abutment formation 503 disposed in the pathof the end portions of the tens-transfer cam member 408 carried by the corresponding actuator gear 406. The spring tension on the dog 498 is such that when the gear 406 is rotating in a positive or counter-clockwise direction, as viewed in Fig. 8, the ends of .the tens-transfer cam will pass the abutment formation 503 and rock the dog relative to the associated latch lever 492 without moving the latch lever out of latching engagement with the corresponding pawl 485. However, when the accumulator gear is rotated in a negative, or clockwise direction, as viewed in Fig. 8, engagement of an end of the tens-transfer cam 408 with the corresponding abutment formation 503 will tend to move the actuating dog 498 relative to the latch lever 492 in a direction in which movement is precluded by the stop arm 501 and stud 502, thereby swinging the latch lever about the shaft 463 in a direction to release the associated transfer pawl 485 and free this pawl to impart a single step or unit space rotational movement to a corresponding accumulator gear. The nose 489 of the negative gear moving assembly is laterally offset to the left from the position of its associated abutment formation 503, in the same manner as in the positive gear rotating assembly, so that, when the tens-transfer cam on one accumulator gear moves the aligned latching lever 492 to release the corresponding transfer pawl 485 and bellcrank lever 446, the nose 489 will engage and impart a one step or unit space rotational movement to the accumulator gear of the next higher order.

With the above-described arrangement, the tens-transfer operation will be carried forward in either a positive or a negative direction, but in each case the tens-carry operation will be made from an accumulator gear passing to or through its 0 position to the accumulator gear of the next higher order immediately to the left of the gear passing to or through its 0 position.

The operation of the tens-transfer mechanism, as described above, is controlled by a bail, generally indicated at 505, the cross, or intermediate, portion 506 of which constitutes an actuating rod 506 extending transversely of the accumulator plate assembly below the distal ends of the legs 441 and 445 of the bellcrank levers 440 and 444. The legs 507 and 508 of the bail 505 are pivotally mounted at the open end of the bail on a shaft 509 which is supported on the end plates of the accumulator plate assembly parallel to, and forwardly of, the shaft 438. A bellcrank lever 510 (Fig. 11) is pivotally mounted at one end on the intermediate frame plate 187 of the machine by a pivotal mounting 511 disposed rearwardly of and below the cam shaft 135. One arm 512 of this bellcrank lever 510 extends forwardly from the pivotal connection 511 and is connected at its forward end to the adjacent end of the bail 506 by a link 513.

A second arm 514 of the bellcrank lever extends upwardly from the leg 512 near the free, or distal, end of the latter and terminates at a location above the tens-transfer 

